Interactive whiteboards have been an active field of research in recent human-computer interaction (HCI) systems composed of various types of sensors, a projector, etc.
In the interactive whiteboard employing an electronic pen, users draw graphics or characters with the electronic pen on the board while the movements of the electronic pen within the board plane are tracked and detected by sensors, and the graphics or characters drawn by the users with the electronic pen are displayed within the board plane. Computer commands may be recognized based on lines of the movements of the electronic pen within the board plane to control the computer operations (e.g., Patent Documents 1 and 2).
The users' operations with the electronic pen on the related art interactive whiteboards are limited to two-dimensional operations; the users are generally not allowed to manipulate contents displayed on a screen of the interactive whiteboard.